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March 16, 2010. (2010-03-16) Life After People is a television series on which scientists, mechanical engineers, and other experts speculate about what might become of planet Earth if humanity suddenly disappeared. The featured experts also talk about the impact of human absence on the environment and the vestiges of civilization thus left behind.
In 1976 two identical Viking program landers each carried four types of biological experiments to the surface of Mars. The first successful Mars landers, Viking 1 and Viking 2, then carried out experiments to look for biosignatures of microbial life on Mars. The landers each used a robotic arm to pick up and place soil samples into sealed test ...
Spontaneous generation is a superseded scientific theory that held that living creatures could arise from nonliving matter and that such processes were commonplace and regular. It was hypothesized that certain forms, such as fleas, could arise from inanimate matter such as dust, or that maggots could arise from dead flesh.
Experiment testing the origin of life. The Miller–Urey experiment was a synthesis of small organic molecules in a mixture of simple gases in a thermal gradient created by heating (right) and cooling (left) the mixture at the same time, with electrical discharges. The Miller–Urey experiment[1](or Miller experiment[2]) was an experiment in ...
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. [ 1 ][ 2 ] All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living and functioning of organisms. [ 3 ] Cell biology is the study of the structural and functional ...
Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life forms on Earth. Evolution holds that all species are related and gradually change over generations. [1]
Life functions through the specialized chemistry of carbon and water, and builds largely upon four key families of chemicals: lipids for cell membranes, carbohydrates such as sugars, amino acids for protein metabolism, and nucleic acid DNA and RNA for the mechanisms of heredity.